Thin-ridge Silicon-on-Insulator waveguides with directional control of lateral leakage radiation

In this paper, we propose a Silicon-On-Insulator waveguide structure which when excited with TM guided light emits controlled TE polarized radiation from one side of the structure only. The validity of the proposed structure is analyzed using eigenmode expansion and supermode techniques. It is shown that care must be taken to select the gap between the radiating elements such that both the phase and the amplitude of the radiating modes are maintained along the propagation direction to achieve the desired directional control of radiation. Steps toward practical demonstration of the proposed structure are identified.